Circuit for controlling key and LED multiplexing IO port

Abstract

The utility model relates to the technical field of display control, in particular to a circuit of a control key and an LED multiplexing IO port. The device is characterized by comprising a multiplexing circuit and a control module, the multiplexing circuit comprises a port LED1 used for being connected with the IO port of the control module. The multiplexing circuit comprises an LED branch circuit and a key branch circuit, one end of the LED branch circuit and one end of the key branch circuit are both connected with the port LED1 in an adaptive mode, and the other end of the LED branch circuit and the other end of the key branch circuit are both grounded. By adopting the circuit, the hardware cost can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of display control, in particular to a circuit for controlling buttons and LED multiplexing IO ports. Background Art

[0002] Currently, the traditional display and case control method uses a chip to control one button or LED with one pin, that is, a one-to-one correspondence between buttons and LEDs. However, in some cases, the chip's pin count may be insufficient, in which case a chip with more pins is needed. However, chips with more pins are more expensive, resulting in higher control hardware costs. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a circuit for controlling buttons and LED multiplexing IO ports, and the use of the circuit can reduce hardware costs.

[0004] To solve the above problems, the following technical solutions are provided:

[0005] The circuit for controlling buttons and LEDs with multiplexed IO ports in this utility model comprises a multiplexing circuit and a control module; the multiplexing circuit includes a port LED1 for connecting to the IO port of the control module. The multiplexing circuit also includes an LED branch and a button branch, one end of each of which is adapted to connect to port LED1, and the other end of each of which is grounded.

[0006] The LED branch includes a light emitting diode D8 , the anode of the light emitting diode D8 is connected to one end of a resistor R27 , the other end of the resistor R27 is connected to the port LED1 via a resistor R37 , and the cathode of the light emitting diode D8 is grounded.

[0007] The button branch includes a button SW-PB_S3, one end of the button SW-PB_S3 is connected to one end of the resistor R34, the other end of the resistor R34 is connected to the port LED1 through the resistor R37, and the other end of the button SW-PB_S3 is grounded.

[0008] The resistance value of the resistor R27 is ≥10*the resistance value of the resistor R34.

[0009] The multiplexing circuit includes a capacitor C13, one end of the capacitor C13 is connected to one end of the resistor R37 connected to the resistor R27, and the other end of the capacitor C13 is grounded.

[0010] The control module contains a chip U2 with model number FU6861N.

[0011] The above solution has the following advantages:

[0012] Because the multiplexing circuit of the control button and LED multiplexing IO port of the utility model includes a port LED1 for connecting to the IO port of the control module, the multiplexing circuit includes an LED branch and a button branch, one end of each of the LED branch and the button branch is adaptively connected to port LED1, and the other end of each of the LED branch and the button branch is grounded. During use, the detection frequency of the IO port of the control module is increased, and then the control module controls the input mode and output mode of the IO port according to the situation, and defines the pin as a different constant for input and output, thereby achieving LED display and button control. Compared with the background art, a single IO port can complete the LED display and button control, greatly reducing the number of chip pins required, thereby eliminating the need to use chips with more pins and reducing hardware costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the circuit structure of the control button and LED multiplexing IO port of the utility model;

[0014] Figure 2 This is a schematic diagram of a multiplexing circuit in a circuit of a control button and LED multiplexing IO port of the present invention;

[0015] Figure 3 It is a schematic diagram of a control module in a circuit of a control button and an LED multiplexing IO port of the utility model. DETAILED DESCRIPTION

[0016] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0017] like Figure 1 and Figure 3 As shown, the circuit of the control button and LED multiplexing IO port of the utility model includes a multiplexing circuit and a control module. The control module contains a chip U2 of model FU6861N, and the chip U2 contains peripheral circuits that drive its operation, such as Figure 3 As shown, the specific structure of the peripheral circuit belongs to the prior art and will not be described here in detail.

[0018] like Figure 2 As shown, the multiplexing circuit includes a port LED1 for connecting to the IO port of the control module. The multiplexing circuit includes an LED branch and a button branch. One end of each LED branch and button branch is adapted to connect to port LED1, and the other end of each LED branch and button branch is grounded. In this embodiment, the IO port is pin 32 of chip U2.

[0019] like Figure 2As shown, in this embodiment, the LED branch includes a light-emitting diode D8, the anode of which is connected to one end of a resistor R27, the other end of which is connected to port LED1 via a resistor R37, and the cathode of which is grounded. The button branch includes a button SW-PB_S3, one end of which is connected to one end of a resistor R34, the other end of which is connected to port LED1 via a resistor R37, and the other end of which is grounded.

[0020] Among them, the resistance value of resistor R27 is ≥10*the resistance value of resistor R34. Figure 2 The resistance of resistor R27 is shown to be 10K ohms, and the resistance of resistor R34 is shown to be 1K ohm.

[0021] In order to avoid external interference, the multiplexing circuit includes a capacitor C13, one end of the capacitor C13 is connected to one end of the resistor R37 connected to the resistor R27, and the other end of the capacitor C13 is grounded.

[0022] During operation, the control module raises the detection frequency of the IO port. The control module then switches the IO port between input and output modes, adjusting the input and output pins to different constants. This allows for both LED display and key control. Specifically, in display mode (i.e., when the IO port is in output mode), the operating voltage of LED D8 is typically above 1.8V. To ensure proper illumination of the LED, the IO port voltage constant can be set so that, after voltage division by resistors R37 and R27, the voltage acting on LED D8 remains above 1.8V, thereby ensuring proper operation in the display mode. In key control mode, the IO port voltage constant can be set so that, after voltage division by resistors R37 and R27, the voltage acting on LED D8 remains below 1.8V, thereby avoiding confusion between the display mode and key control mode. Furthermore, the resistance of resistor R27 is ≥10*the resistance of resistor R34. In key control mode, pressing a key short-circuits the LED display branch, thus ensuring the stability of the key control mode. The specific voltage constant value of the IO port belongs to the existing technology and will not be described here.

Claims

1. A circuit for controlling buttons and LEDs to multiplex IO ports, characterized in that: It includes a multiplexing circuit and a control module; the multiplexing circuit includes a port LED1 for connecting to the IO port of the control module; the multiplexing circuit includes an LED branch and a button branch, one end of the LED branch and the button branch are both adapted to be connected to the port LED1, and the other ends of the LED branch and the button branch are both grounded.

2. The circuit for controlling buttons and LEDs to multiplex IO ports as claimed in claim 1, wherein: The LED branch includes a light emitting diode D8 , the anode of the light emitting diode D8 is connected to one end of a resistor R27 , the other end of the resistor R27 is connected to the port LED1 via a resistor R37 , and the cathode of the light emitting diode D8 is grounded.

3. The circuit for controlling buttons and LEDs to multiplex IO ports as claimed in claim 2, wherein: The button branch includes a button SW-PB_S3, one end of the button SW-PB_S3 is connected to one end of the resistor R34, the other end of the resistor R34 is connected to the port LED1 through the resistor R37, and the other end of the button SW-PB_S3 is grounded.

4. The circuit for controlling buttons and LEDs to multiplex IO ports as claimed in claim 3, wherein: The resistance value of the resistor R27 is ≥10*the resistance value of the resistor R34.

5. The circuit for controlling buttons and LEDs to multiplex IO ports as claimed in claim 4, characterized in that: The multiplexing circuit includes a capacitor C13, one end of the capacitor C13 is connected to one end of the resistor R37 connected to the resistor R27, and the other end of the capacitor C13 is grounded.

6. The circuit for multiplexing IO ports of a control button and an LED according to any one of claims 1 to 5, characterized in that: The control module contains a chip U2 with model number FU6861N.

Images